Take an empty Sodastream carbonator to a local retailer to exchange it and receive a full carbonator. As of 2015, Target, Walmart and Best Buy sell Sodastream supplies and exchange carbonators. Visit Sodastream's website to check for a current list of participating retailers.
Sodastream carbonators, which come in 60-liter and 130-liter sizes, are exchanged at participating retailers for the cost of the carbon dioxide gas. The larger 130-liter tank is not available at all locations. Some sparkling-water kits include a starter or mini carbonator, which are both under 16 liters, and they can be exchanged for either the 60-liter or 130-liter carbonator for the price of the gas. The smaller starter tanks are not available for the exchange.
Due to regulations by the U.S. Department of Transportation, the gas in Sodastream carbonators is considered a hazardous material, and therefore cannot be shipped or picked up by UPS or FedEx. Exchange carbonators are no longer available for sale online from Sodastream, but spare carbonators are still available for purchase, which can be shipped to your home and exchanged at participating retailers for a full tank. Some local retailers also sell spare carbonators. Check with the participating retailer for a detailed list of services and products.